Today I checked on this game and it is quite good. The medals are working. I could only complain a bit about the controls that are clumsy sometimes. There are monets when the second jump fails to work for some reason. You could make a version or add an update with a level select if somebody passed certain levels, because passing the same easier levels over and over again if you want to get to the current challenge is a bit tedious. I know it is supposed to be retro, but now we got progress saving etc. I was actually playing these types of games when I was a kid and I admit that I am happy that game development made a significant progress from that time. Another thing I could complain a bit are the not necessarily precise hitboxes. It is also a bit annoying that you cannot simply stand on the top of the ladder, the character's behavior is a bit weird there.
I like the level design. It forces you to plan ahead, think of what you are supposed to do and when. What's more, if you are going for 100% on a level it is possible to screw up and be forced to start from the scratch.
So, with several improvements here and there it can be a really good game, deserving definitely more than its current score.